Area Forecast Discussion
Issued by NWS Dodge City, KS
Issued by NWS Dodge City, KS
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313 FXUS63 KDDC 070647 AFDDDC Area Forecast Discussion National Weather Service Dodge City KS 147 AM CDT Fri Jun 7 2024 .KEY MESSAGES... - First 100-degree heat forecast across far southwest Kansas tomorrow. (50-60% probability of exceedance 100+ degrees for Liberal, Elkhart, Johnson, Hugoton, Ulysses) - Scattered early Friday morning showers and thunderstorms mainly between Ark River and Oklahoma line, followed by another chance of storms later in the afternoon and Friday Night. Marginal Risk (1 of 5) of severe weather - Increased likelihood of large thunderstorm system Saturday Night with POPs increased to 60% for much of the southwest Kansas region. && .SHORT TERM /THROUGH SATURDAY/... Issued at 342 PM CDT Thu Jun 6 2024 This afternoon, water vapor loop and RAP analysis showed a broad ridge of high pressure extending across much of the western and central CONUS, which was allowing temperatures to really heat up across the Southwest and into New Mexico. Roswell, NM was baking in 104F heat as of 1950Z. This heat will make a run on much of our forecast area tomorrow. In the meantime, a cold front passage earlier this morning kept our temperatures at bay across southwest Kansas, but mid to upper 80s were observed from the Ark River south to the Oklahoma line. The front to our south will stall out and return north as a warm from tonight/early Friday morning. The frontal zone in the 800-700mb layer will likely provide enough upward vertical motion due to increased warm frontogenesis in the 09-15Z time frame. The convection allowing models (CAMs) are not too excited about early Friday morning storms, but the NAM12 and GFS20 (non-CAM models) are more aggressive with their QPF development along the 800-700mb frontal zone across the southern third of our forecast area (mainly along/south of the Ark River). The HRRR runs do show some signal in its Composite Reflectivity, but the HRRR model does not have very aggressive thunderstorm development. We will keep 20-30 POPs going early in the morning given the aforementioned frontogenetic forcing for ascent, but leaning more toward just widely scattered non-severe convection at this point. Later in the day Friday, a dryline will develop with temperatures really warming up along/west of the dryline. There is strong consensus among all models, including short term CAMs, of at least a quarter to a third of the forecast area (far southwest Kansas) reaching 100 degrees in the mid-late afternoon before any thunderstorms develop. So, official forecast highs will be 100 or 101 for areas like Liberal, Elkhart, Hugoton, Johnson, and Ulysses. Elsewhere east of the dryline, temperatures will likely top out in the lower to mid 90s. Later in the afternoon and evening Friday, the focus will shift to renewed surface-based thunderstorm development. All models show thunderstorm activity developing and/or moving into western Kansas. The question then comes down into the details. How much of the thunderstorm activity will be what moves in from Colorado vs. how much of our activity in southwest Kansas will be from pristine development along the trough axis/dryline to the east of the Colorado line. Colorado storms will initially develop in drier air where convective temperature is reached first (i.e. 0-3km AGL lapse rates becoming dry adiabatic). Regardless, we will not be looking at a significant severe weather event as the main forcing for ascent and greater deep layer wind shear will be up across Nebraska, so the SPC Day Two Marginal Risk (Level 1 of 5) is a good forecast at this point. The likelihood of a nocturnal mesoscale convective system (MCS) sweeping across our southwest Kansas region is rather low with the main MCS signal well to our northeast. && .LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/... Issued at 342 PM CDT Thu Jun 6 2024 Over the past several forecast cycles, the best signal for the most numerous thunderstorm activity across west central/southwest Kansas has been the Saturday Night period. This thinking has not changed, and in fact there is now growing confidence in a fairly robust MCS or two tracking across much of western/central Kansas Saturday Night. For this reason, the Saturday Night period POPs have been increased to "Likely" 55+ percent across nearly the entire forecast area with the exception of our eastern counties. A significant Saturday Night MCS will almost assuredly have impacts on Sunday`s sensible weather. For this reason, Sunday`s forecast is less confident, but low level moisture will be around and almost all models show low level winds in a favorable east/southeast upslope direction with mid to upper 60s dewpoints pulling back west into southwest Kansas. The 64-thousand dollar question, though, is how worked over the boundary layer will be and will there be enough recovery for another MCS Sunday evening/night. The best forecast is that the axis of best MCS probability Sunday Night will be a bit farther south than where Saturday Night`s MCS will be. After Sunday Night, the pattern becomes complicated with an upper low likely off the coast of southern California/Baja and the main polar jet well to the north along the Canada line. Eventually, the cutoff upper level low will eject northeast across the Intermountain West/Rockies, but there is a lot of model difference in the evolution of this going into mid to late next week. && .AVIATION /06Z TAFS THROUGH 06Z SATURDAY/... Issued at 1202 AM CDT Fri Jun 7 2024 Satellite showed clear sky across the entire area at 5z and this will continue for several more hours. By the 12z 18z window, warm advection will promote isolated to widely scattered shower and thunderstorms that may impact LBL and GCK by 15z and DDC thereafter. Still its a low probability at around 20%, for non- severe TSRA. Winds will pick up to around 15-25 knots with higher gusts by late morning and through the afternoon areawide before severe storms move into western Kansas after 22 UTC bringing slight chances (20-40%) for convection to impact area terminals through about 6z. && .DDC WATCHES/WARNINGS/ADVISORIES... None. && $$ SHORT TERM...Umscheid LONG TERM...Umscheid AVIATION...Russell